A need has long existed for a flame proof wallboard for dwellings, hospitals, and other public buildings to take the place of marble, tile, and other hard fire proof surfacing materials which are now too expensive for general use in the building industry. The usual drywall board comprising gypsum between two layers of paper is not sufficiently fire resistant for hospitals and public buildings, nor is the painted fiber board that is presently available. Concrete materials are not sufficiently strong to resist scratching and they are too porous to meet santitary codes for hospitals. The same is generally true of cement bonded fiber boards, such as masonite, etc.
Accordingly, it is an object of the present invention to produce an inexpensive light weight paneling which has a surface which has a very low flame spread rate, that liberates very little smoke when subjected to temperatures of 1,000.degree. F or more, and which contributes practically no fuel to a fire that is contained by the paneling.
Another object of the present invention is the provision of a wallboard of the above described type having a smooth dense surface that cannot be scratched by a carbon steel knife.
Another object of the present invention is the provision of a new and improved molding compound for producing such fire resistant surfaces.
Another object of the invention is the provision of a new and improved retarder-catalyst system for aldehyde condensate resins.
A further object of the present invention is the provision of a new and improved method of making a fiber board.